In the field of machine tools, a workpiece is conventionally attached to a pallet which is detachably attached to a table of a machine tool whereby the workpiece is processed. In such machine tools, a non-processed workpiece and a processed workpiece, each attached to a pallet, are exchanged with each other by a pallet changer.
Patent Document 1, for example, discloses a pallet changer which is provided with an arm member, rotatable about an axis inclined by 45 degrees relative to a horizontal plane. The arm member has a pair of pallet supports, symmetrically disposed relative to the inclined axis of the arm member, whereby the rotation of the arm member exchanges the pallet supports between a pallet changing position and a work changing position.
Patent Document 1: Japanese Unexamined Patent Publication No. H07-171730